Air Diffuser

ABSTRACT

An air diffuser includes a body having a body having a substantially flat upper surface and a concave lower surface. A plurality of slots is formed through the body in fluid communication with the upper and lower surfaces. A flow modulator is rotatably affixed to the lower surface, the flow modulator having a plurality of slots configured to selectably cover the slots in the body. The flow modulator and a junction between the flow modulator and the lower surface are configured to provide a substantially constant flow velocity through the slots independent of a rotational position of the flow modulator.

CROSS REFERENCE TO RELATED APPLICATION

This Application claims the benefit of U.S. Provisional Application No. 60/725,805, filed Oct. 12, 2005.

FIELD OF THE INVENTION

The present invention is directed to an air diffuser for use with an HVAC system, and more particularly, is directed to a floor mounted air diffuser.

BACKGROUND OF THE INVENTION

Air diffusers are important components of an HVAC system. Air diffusers are important because they deliver air from the HVAC system to areas within a structure, providing enhanced comfort to those inside the structure. Many air diffusers can be adjusted to modulate the amount of air that flows through the air diffuser. However, with known air diffuser constructions, a reduction in the volume of airflow through the air diffuser similarly results in a reduction in the velocity of the air flowing through the air diffuser, which is referred to as “face velocity.” These reductions in the face velocity can result in “puddling,” in which air flowing through the air diffuser has insufficient velocity to be distributed or “thrown” into the room, and thus accumulates or puddles adjacent to the air diffuser. Puddling may result in an uneven temperature distribution within the structure, which is undesirable.

What is needed is an adjustable volume air diffuser that provides a substantially constant face velocity and reduces or eliminates inefficiencies resulting from phenomenon such as puddling.

SUMMARY OF THE INVENTION

The present invention relates to an air diffuser including a body having a substantially flat upper surface and a concave lower surface. A plurality of slots is formed through the body in fluid communication with the upper and lower surfaces. A flow modulator is rotatably affixed to the lower surface, the flow modulator having a plurality of slots configured to selectably cover the slots in the body. The flow modulator and a junction between the flow modulator and the lower surface are configured to provide a substantially constant flow velocity through the slots independent of a rotational position of the flow modulator.

The present invention further relates to a method for substantially reducing puddling adjacent an air diffuser of an HVAC system. The method includes the comprising the step of providing the air diffuser, the air diffuser being configured so that air from the HVAC system flows through the air diffuser. The air diffuser includes a body having a substantially flat upper surface and a concave lower surface. A plurality of slots is formed through the body in fluid communication with the upper and lower surfaces. A flow modulator is rotatably affixed to the lower surface, the flow modulator having a plurality of slots configured to selectably cover the slots in the body. The flow modulator and a junction between the flow modulator and the lower surface are configured to provide a sufficiently constant flow velocity through the slots independent of a rotational position of the flow modulator to substantially eliminate puddling adjacent the air diffuser.

An advantage of the present invention is that it is inexpensive to manufacture.

A further advantage of the present invention is that it provides a substantially constant face velocity.

A still further advantage of the present invention is that it provides a substantially constant face velocity over substantially the entire range of flow modulation.

Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are typically not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an air diffuser of the present invention.

FIG. 2 is an exploded view of an air diffuser of the present invention.

FIG. 3 is a plan view of an air diffuser of the present invention.

FIG. 4 is a cross-section of an air diffuser taken along line 4-4 of FIG. 3 of the present invention.

FIG. 5 is a cross-section of an air diffuser taken along line 5-5 of FIG. 3 of the present invention.

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are typically not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

One embodiment of an air diffuser 10 is shown in FIGS. 1-3. Air diffuser 10 includes a body 12 having a preferably flat upper surface 14 and a lower surface 16 having a substantially concave portion 50 (see e.g., FIG. 4). Preferably, the concave portion 50 defines a hemispherical dome profile, but includes a substantially coplanar or flat portion 44 (FIG. 5) disposed along the periphery of the lower surface 16 to more evenly distribute forces applied against the upper surface 14. Air diffuser 10 is preferably received in a recess formed in a floor or raised platform of a structure, such as a plenum (not shown) so that the upper surface 14 is substantially flush with a surface of the structure. A plurality of through slots 18 are formed in the body 12 for permitting air provided to the lower surface 16 of the air diffuser 10 by an HVAC system (not shown) to pass through the slots 18 for delivery of the air to a space inside the structure. The slots 18 are configured such that air is provided through upper surface 14 at a substantially constant face velocity, which prevents puddling of the air adjacent the air diffuser 10.

The air diffuser 10 can also modulate the flow of air delivered by the slots 18 through upper surface 14. A flow modulator 20 is rotatably affixed to the lower surface 16 of body 12 by fasteners 24, 28 passing through respective centered apertures 26, 22. Preferably, aperture 22 includes a counter bore so that the head of fastener 24 is substantially flush with the upper surface 14, the fastener 24 preferably having a slot 25 formed in the head of the fastener 24, which slot 25 having a geometry suitable for engagement with a coin or similar device for ease of rotational adjustment of the flow modulator 20. The flow modulator 20 includes a plurality of slots 19 preferably sized and arranged substantially identical to the slots 18 in body 12 to modulate the volume of air flowing through the slots 18 and past the upper surface 14 of the body 12. At one extreme, corresponding to a first position of the flow modulator 20 with respect to the body 12, the slots 19 of the flow modulator 20 are aligned with the slots 18 of the of body 12, so that the slots 18 are not obstructed by the flow modulator 20. At the other extreme, corresponding to a second position of the flow modulator 20 with respect to the body 12, the slots 19 of the flow modulator 20 are misaligned with the slots 18 of the of body 12, so that the slots 18 are maximally obstructed by the flow modulator 20. Preferably, in the maximally obstructed position, flow modulator 20 substantially obstructs the flow of air through the slots 18.

However, not including the maximally obstructed position, or a position sufficiently adjacent to the maximally obstructed position such that the flow of air through the slots 18 is substantially obstructed, the airflow through the slots 18 is delivered at a substantially constant face velocity. This is due to the sealing arrangement and closeness or substantial lack of space between the flow modulator 20 and the lower surface of the body 12. The flow modulator 20 is preferably a thin sheet of material. Because the lower surface 16 of the body 12 is concave, and more preferably, hemispherical (see e.g., FIGS. 4 and 5), the surface of the flow modulator 20 closely conforms to the lower surface 16, providing a substantially fluid tight fit therebetween when fasteners 24, 28 are sufficiently mechanically engaged. Close proximity between the flow modulator 20 and the lower surface 16 is possible because of the minimal thickness dimension of flow modulator 20 and the conformal fit between the flow modulator 20 and the lower surface 16. Additionally, due to this close proximity, even with misalignment between slots 18 of the body 12 and slots 19 of the flow modulator 20 resulting in partial obstruction of slots 18 and a reduced volume of airflow through the body 12, the face velocity remains substantially unchanged. Stated another way, although the misalignment results in a reduced volume of airflow through the slots 18, the reduction of effective surface area of the slots 18 is also similarly reduced, thus substantially maintaining the velocity of the air flowing through the slots 18. By providing substantially constant face velocity over the range of airflow through the air diffuser, enhanced comfort can be achieved for an occupant of a structure desiring less air flow from an adjacent air diffuser, since the reduced air flow will still be delivered at a velocity sufficient to mix with adjacent air in the structure, without the disadvantages of puddling. Mathematically, this relationship can be represented in equation 1 V=Q/A  [1] where V is velocity, Q is flow and A is area. In other words, due to the close proximity between the flow modulator 20 and the lower surface 16, as well as the fluid tight fit therebetween, varying the flow area to throttle the flow volume yields a substantially constant flow velocity over substantially the entire range of obstruction provided by the flow modulator 20. A constant flow velocity then aids in consistent distribution or “throw” of air into the space of a structure.

Referring to FIGS. 3-5, slots 18 of a preferred embodiment are discussed, based on dividing the upper surface 14 into a plurality of predetermined regions, preferably substantially equally sized regions, such as quadrants 34, 36, 38, 40 defined by a horizontal axis 30 and a vertical axis 32 that intersect at the centerline of aperture 22. A group of identically arranged and configured slots S1, S2, S3 is contained in each of diagonally opposed quadrants 34 and 38. Similarly, a group of identically arranged and configured slots S4, S5, S6, S7 is contained in each of diagonally opposed quadrants 36 and 40. Preferably, each of the slots is radially disposed from aperture 22, with the opposed walls of each of the slots being substantially straight and parallel to each other. In a preferred embodiment, the surfaces of the slot walls are substantially smooth. An inner wall of each of the slots S1, S2, S3 is spaced from aperture 22 by respective radii R1, R2 and R3 as measured from the center of aperture 22 along the upper surface 14, which slots preferably being equally spaced from each other. Similarly, an inner wall of each of the slots S4, S5, S6, S7 is spaced from aperture 22 by respective radii R4, R5, R6, R7 as measured from the center of aperture 22 along the upper surface 14, which slots preferably being equally spaced from each other. Additionally, the ends of each of the slots S1-S7 are preferably substantially equally spaced from their respective horizontal and vertical axes 30, 32 that define each quadrant. That is, the horizontal distance (“DH”) is the distance from the center of the semicircle defining an edge of the slot and the vertical axis 32, while the vertical distance (“DV”) is the distance from the center of the semicircle defining an edge of the slot and the horizontal axis 30.

The angular orientation of slots S1, S2, S3 are respective angles A1, A2 A3 as measured from an axis 48 extending through aperture 22 and perpendicular to the upper surface 14. Similarly, the angular orientation of slots S4, S5, S6, S7 are respective angles A4, A5, A6, A7 as measured from an axis 48 extending through aperture 22 that is perpendicular to the upper surface 14. For each grouping of slots, the angles increase with increased radial distance of the slot from aperture 22 as measured along the upper surface 14. Preferably, the increase in angular measurement between each of A1-A3 and between each of A4-A7 is substantially uniform and is substantially the same between each of A1-A7. For example, in one embodiment, the difference in angular measurement between each of A1-A3 and of A4-A7 is five degrees, with A1 being 32.5 degrees and A4 being 30 degrees. Although this range of angles provides a beneficial funnel effect, it is it to be understood that the invention is not limited to the angular measurements described above. In other words, the angular amounts can vary upwardly or downwardly from the amounts provided, and the difference in angular measurement between adjacent slots does not necessarily increase in uniform increments.

Components of the air diffuser 10 can be constructed of metal, a polymer, a combination thereof, although it is to be understood that the invention is not limited to those materials, since other materials having sufficient structural strength and compatibility for use with HVAC systems can also be used. It is also to be understood that the slots formed in the body 12 are not required to be radially disposed, nor are the slot angles required to increase as a function of increased slot distance from the center of the body 12. It is also not required that symmetry exist between any of the slots formed in the body 12, nor that the slots are uniformly spaced. In addition, it is not required that any of the slot walls be parallel to each other, nor that the slot wall are substantially or even partially smooth. Further, the body 12 can be non-circular, such as square, rectangular, oval or define other geometric shapes.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. 

1. An air diffuser comprising: a body having a substantially flat upper surface and a concave lower surface; a plurality of slots formed through the body in fluid communication with the upper and lower surfaces; a flow modulator rotatably affixed to the lower surface, the flow modulator having a plurality of slots configured to selectably cover the slots in the body; and wherein the flow modulator and a junction between the flow modulator and the lower surface being configured to provide a substantially constant flow velocity through the slots independent of a rotational position of the flow modulator.
 2. The air diffuser of claim 1 wherein the junction is a contact surface between the upper and lower surfaces.
 3. The air diffuser of claim 1 wherein the junction forms a substantially fluid tight seal between the upper and lower surfaces.
 4. The air diffuser of claim 1 wherein the periphery of the lower surface includes a substantially flat portion.
 5. The air diffuser of claim 1 wherein the upper surface is divided into a plurality of predetermined regions.
 6. The air diffuser of claim 1 wherein the plurality of slots is arranged based on a plurality of predetermined regions.
 7. The air diffuser of claim 4 wherein the plurality of slots is radially disposed.
 8. The air diffuser of claim 3 wherein the plurality of regions are substantially equally sized.
 9. The air diffuser of claim 1 wherein the plurality of slots is arranged based on a plurality of substantially equally sized regions.
 10. The air diffuser of claim 7 wherein the plurality of slots is radially disposed.
 11. The air diffuser of claim 6 wherein each region defines a quadrants.
 12. The air diffuser of claim 1 wherein the plurality of slots is radially disposed and arranged based on quadrants.
 13. The air diffuser of claim 12 wherein the ends of each slot is substantially equally spaced from axes defining the quadrants.
 14. The air diffuser of claim 1 wherein at least one surface of each slot is angled from the upper surface.
 15. The air diffuser of claim 14 wherein the angles of the at least one surface of adjacent slots increase with increased radial distance from a predetermined point.
 16. The air diffuser of claim 15 wherein the amount of increase of angles of the at least one surface is substantially the same between adjacent slots.
 17. The air diffuser of claim 14 wherein the angles of the at least one surface increase with increased radial distance from a predetermined point.
 18. The air diffuser of claim 17 wherein the distance between opposed surfaces of each slot is substantially equal.
 19. The air diffuser of claim 12 wherein the plurality of slots of diagonally opposed quadrants are substantially symmetric.
 20. A method for substantially reducing puddling adjacent an air diffuser of an HVAC system, comprising the step of: providing the air diffuser, the air diffuser being configured so that air from the HVAC system flows through the air diffuser, the air diffuser comprising: a body having a substantially flat upper surface and a concave lower surface; a plurality of slots formed through the body in fluid communication with the upper and lower surfaces; a flow modulator rotatably affixed to the lower surface, the flow modulator having a plurality of slots configured to selectably cover the slots in the body; and wherein the flow modulator and a junction between the flow modulator and the lower surface are configured to provide a sufficiently constant flow velocity through the slots independent of a rotational position of the flow modulator to substantially eliminate puddling adjacent the air diffuser. 